There is a conventional plate laminated type heat exchanger that includes a plurality of waveform plates which are laminated and bonded to each other. Each waveform plate has a plurality of recessed portion as flow channels of fluid on a surface thereof (For example, see Japanese Unexamined Patent Application Publication No. 2002-62085). In addition, there is a conventional plate laminated type heat exchanger formed from flat plates bonded to each other by diffusion bonding (For example, Japanese Unexamined Patent Application Publication No. Sho 61-62795 and Japanese Unexamined Patent Application Publication (Translation of PCT Application) No. 2008-535261).